The term 'Bit of Roofing' can be solved by the four-letter word 'TILE'. Tiles are a common material used in roofing, and have been used for centuries. They are made from clay, concrete, or other materials, and are usually shaped into flat pieces with a curved top. Tiles are laid in overlapping rows to form a waterproof barrier on the roof. They are also used for decorative purposes, and come in a variety of colors and styles.